U.S. patent number 4,102,798 [Application Number 05/708,925] was granted by the patent office on 1978-07-25 for oxazoline additives useful in oleaginous compositions.
This patent grant is currently assigned to Exxon Research & Engineering Co.. Invention is credited to Stanley J. Brois, Harold N. Miller, Jack Ryer, James Zielinski.
United States Patent |
4,102,798 |
Ryer , et al. |
July 25, 1978 |
Oxazoline additives useful in oleaginous compositions
Abstract
Oil soluble oxazoline reaction products of hydrocarbon
substituted dicarboxylic acid, ester, or anhydride, for example
polyisobutenylsuccinic anhydride, with
2,2-disubstituted-2-amino-1-alkanols, such as
tris-hydroxymethylaminomethane (THAM), are useful additives in
oleaginous compositions, such as sludge dispersants for lubricating
oil or gasoline.
Inventors: |
Ryer; Jack (East Brunswick,
NJ), Zielinski; James (Somerset, NJ), Miller; Harold
N. (Millington, NJ), Brois; Stanley J. (Westfield,
NJ) |
Assignee: |
Exxon Research & Engineering
Co. (Linden, NJ)
|
Family
ID: |
23808036 |
Appl.
No.: |
05/708,925 |
Filed: |
July 27, 1976 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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455250 |
Mar 27, 1974 |
|
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Current U.S.
Class: |
508/278;
548/238 |
Current CPC
Class: |
C10L
1/238 (20130101); C10L 1/233 (20130101); C07D
263/14 (20130101); C07D 263/12 (20130101); C10M
1/08 (20130101); C10L 1/303 (20130101); C08F
8/32 (20130101); C10L 1/221 (20130101); C07F
9/653 (20130101); C08G 63/685 (20130101); C10L
1/2691 (20130101); C08F 8/32 (20130101); C08F
10/00 (20130101); C10M 2205/14 (20130101); C10M
2207/34 (20130101); C10M 2207/024 (20130101); C10M
2215/042 (20130101); C10M 2225/041 (20130101); C10M
2207/121 (20130101); C10M 2219/089 (20130101); C10M
2215/221 (20130101); C10M 2215/22 (20130101); C10M
2223/08 (20130101); C10N 2010/04 (20130101); C10M
2209/109 (20130101); C10N 2070/02 (20200501); C10M
2217/043 (20130101); C10M 2223/00 (20130101); C10N
2040/044 (20200501); C10N 2040/046 (20200501); C10M
2207/028 (20130101); C10M 2215/28 (20130101); C10M
2223/042 (20130101); C10M 2227/061 (20130101); C10M
2207/122 (20130101); C10M 2215/225 (20130101); C10M
2219/088 (20130101); C10M 2223/045 (20130101); C10M
2205/022 (20130101); C10M 2223/04 (20130101); C10N
2040/04 (20130101); C10M 2207/027 (20130101); C10M
2215/04 (20130101); C10M 2219/087 (20130101); C10M
2229/02 (20130101); C10M 2219/044 (20130101); C10M
2205/026 (20130101); C10M 2207/023 (20130101); C10N
2040/253 (20200501); C10M 2223/061 (20130101); C10M
2205/00 (20130101); C10M 2223/065 (20130101); C10M
2209/086 (20130101); C10M 2215/065 (20130101); C10M
2215/086 (20130101); C10M 2217/046 (20130101); C10M
2209/084 (20130101); C10M 2211/02 (20130101); C10M
2290/02 (20130101); C10M 2215/30 (20130101); C10N
2040/02 (20130101); C10N 2040/08 (20130101); C10M
2215/226 (20130101); C10N 2040/042 (20200501); C10M
2207/282 (20130101); C10M 2209/112 (20130101); C10M
2217/042 (20130101); C10N 2040/252 (20200501); C10M
2207/32 (20130101); C10M 2223/06 (20130101); C10M
2229/05 (20130101); C10M 2215/26 (20130101); C10M
2217/06 (20130101); C10M 2223/12 (20130101); C10M
2225/04 (20130101); C10M 2223/041 (20130101); C10M
2219/046 (20130101); C10M 2227/00 (20130101); C10N
2050/10 (20130101) |
Current International
Class: |
C10L
1/26 (20060101); C10L 1/22 (20060101); C10L
1/30 (20060101); C10L 1/233 (20060101); C10L
1/238 (20060101); C07D 263/14 (20060101); C07D
263/12 (20060101); C07D 263/00 (20060101); C07F
9/00 (20060101); C08G 63/00 (20060101); C08F
8/00 (20060101); C08G 63/685 (20060101); C07F
9/653 (20060101); C08F 8/32 (20060101); C10L
1/10 (20060101); C10M 001/32 () |
Field of
Search: |
;252/51.5R,51.5A
;260/37F |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Gantz; Delbert E.
Assistant Examiner: Metz; Andrew H.
Attorney, Agent or Firm: Johmann; Frank T. Dexter; Roland
A.
Parent Case Text
This is a continuation, of application Ser. No. 455,250, filed Mar.
27, 1974 now abandoned.
Claims
What is claimed is:
1. A lubricating oil composition comprising: a major amount of
lubricating oil and 0.01 to 20 wt. % of bis-oxazoline of a molar
proportion of a hydrocarbon-substituted C.sub.4 -C.sub.10
dicarboxylic acid material selected from the group consisting of
dicarboxylic acid, ester and anhydrides thereof, having more than
50 carbon atoms in said hydrocarbon substituent; reacted with about
two molar proportions of a 2,2-disubstituted-2-amino-1-alkanol
having 2 to 3 hydroxy groups and containing a total of 4 to 8
carbons of the formula: ##STR6## wherein X is alkyl or hydroxy
alkyl, said alkyl groups having 1 to 3 carbon atoms, and at least
one of said X is a hydroxy alkyl group of the structure
--(CH.sub.2).sub.n OH where n is 1 to 3; at a temperature in the
range of about 140.degree. to 240.degree. C for about 1/2 to 24
hours with the removal of about three molar proportions of
water.
2. A composition according to claim 1, wherein said
hydrocarbon-substituted dicarboxylic acid material is alkenyl
succinic anhydride.
3. A composition according to claim 2, wherein said amino-1-alkanol
is 2-amino-2-methyl-1-propanol.
4. A composition according to claim 2, wherein said amino-1-alkanol
is tris-(hydroxymethyl)aminomethane.
5. An additive concentrate comprising: a major amount of mineral
lubricating oil in the range of 98 to 45 parts by weight, 2 to 45
parts by weight of bis-oxazoline of a molar proportion of a
hydrocarbon-substituted C.sub.4 -C.sub.10 dicarboxylic acid
material selected from the group consisting of dicarboxylic acid,
ester and anhydrides thereof, having more than 50 carbon atoms in
said hydrocarbon substituent; reacted with about two molar
proportions of a 2,2-disubstituted-2-amino-1-alkanol having 2 to 3
hydroxy groups and containing a total of 4 to 8 carbons of the
formula: ##STR7## wherein X is alkyl or hydroxy alkyl, said alkyl
groups having 1 to 3 carbon atoms, and at least one of said X is a
hydroxy alkyl group of the structure --(CH.sub.2).sub.n OH where n
is 1 to 3; at a temperature in the range of about 140.degree. to
240.degree. C for about 1/2 to 24 hours with the removal of about
three molar proportions of water.
6. A concentrate according to claim 5, wherein said hydrocarbon
substituted dicarboxylic acid is alkenyl succinic anhydride.
7. A concentrate according to claim 6, wherein said amino alcohol
is 2-amino-2-methyl-1-propanol.
8. A composition according to claim 6, wherein said amino alcohol
is tris-(hydroxymethyl)aminomethane.
9. An oil-soluble, oxazoline reaction product obtained from heating
together a molar equivalent of a hydrocarbon substituted C.sub.4
-C.sub.10 dicarboxylic acid material having more than 50 carbon
atoms per dicarboxylic acid group, and two molar equivalents of a
2,2-disubstituted-2-amino-1-alkanol having the formula ##STR8##
wherein X is alkyl or hydroxy alkyl, said alkyl groups having 1 to
3 carbon atoms, and at least one of said X is a hydroxy alkyl group
of the structure --(CH.sub.2).sub.n OH where n is 1 to 3 at a
temperature of from 140.degree.-240.degree. C. until cessation of
water evolution indicating completion of the oxazoline
reaction.
10. An oil-soluble reaction product according to claim 9 wherein
said acid material is selected from the group consisting of acids,
anhydrides and esters and both of said Xs of said amino-1-alkanol
formula are hydroxy alkyl groups of the structure
--(CH.sub.2).sub.n OH wherein n is 1 to 3.
11. An oil soluble reaction product according to claim 9, wherein
said hydrocarbon substituted dicarboxylic acid material is an
alkenyl succinic anhydride and said amino-alkanol is
tris-(hydroxymethyl) aminomethane.
12. A reaction product according to claim 11, wherein said alkenyl
group comprises principally a polymer of C.sub.2 -C.sub.5
monoolefin.
13. A process for preparing the reaction product of claim 9, by
heating to about 180.degree. to 220.degree. C a mixture of
dicarboxylic acid material and said amino-alkanol, and removing a
stoichiometric amount of water by continuing said heating for from
about 2 to 8 hours.
14. A bisoxazoline reaction product prepared by the reaction of a
molar proportion of a hydrocarbon substituted C.sub.4 -C.sub.10
dicarboxylic acid material having more than 50 carbon atoms per
dicarboxylic acid group and two molar proportions of a
2,2-disubstituted-2-amino-1-alkanol having the formula ##STR9##
wherein X is alkyl or hydroxy alkyl, said alkyl groups having 1 to
3 carbon atoms, and at least one of said X is a hydroxy alkyl group
of the structure --(CH.sub.2).sub.n OH where n is 1 to 3 at a
temperature of from 140.degree.-240.degree. C. until cessation of
water evolution indicating completion of the oxazoline
reaction.
15. A bis-oxazoline reaction product according to claim 14 wherein
said reaction is carried out at a temperature of from
140.degree.-240.degree. C and for a time period determined by the
evolution of about three molar proportions of water.
16. A composition according to claim 9, wherein said time is about
2 to 8 hours.
17. A composition according to claim 14, wherein said temperature
is about 180.degree. to 220.degree. C. and said time is about 2 to
8 hours.
18. A bis-oxazoline of the general formula ##STR10## where X is an
alkyl or hydroxy alkyl group said alkyl groups having 1 to 3 carbon
atoms with at least one of the X substituents on each ring being a
hydroxy alkyl group of the structure --(CH.sub.2).sub.n OH wherein
n is 1 to 3 and R is a substantially saturated hydrocarbyl group
containing at least 50 carbon atoms and m is from 0 to 6.
19. A bis-oxazoline according to claim 18 in which all of the X
substituents are hydroxy alkyl groups of the structure
--(CH.sub.2).sub.n OH wherein n is 1 to 3.
20. A bis-oxazoline according to claim 18 in which n is 1.
21. A bis-oxazoline according to claim 18 in which R is an olefin
polymer.
22. A bis-oxazoline according to claim 21 in which the olefin is
isobutylene.
23. A bis-oxazoline according to claim 21 in which the olefin
polymer is of molecular weight from 10,000 to 200,000.
24. A process of preparing a bis-oxazoline comprising reacting a
molar proportion of a substantially saturated
hydrocarbyl-substituted C.sub.4 -C.sub.10 dicarboxylic acid or
anhydride or ester thereof having at least 50 carbon atoms in said
hydrocarbyl group with 2 molar proportions of a
2,2-disubstituted-2-amino-1-alkanol having 2 to 3 hydroxy groups
and containing a total of 4 to 8 carbons of the formula ##STR11##
wherein X is alkyl or hydroxyalkyl, said alkyl groups having 1 to 3
carbon atoms, and at least one of said X is a hydroxy alkyl group
of the structure --(CH.sub.2).sub.n OH where n is 1 to 3, at a
temperature in the range of 140.degree. to 240.degree. C. for 1/2
to 24 hours with the removal of three molar proportions of
water.
25. The process according to claim 24 wherein said reaction is
carried out at a temperature ranging from 180.degree. to
220.degree. C. for 2 to 8 hours.
26. The process according to claim 25 wherein said hydrocarbyl
group is an alkenyl group.
27. The process according to claim 25 wherein said hydrocarbyl
group is a polyisobutenyl group.
28. The process according to claim 25 wherein said anhydride is
succinic anhydride.
29. The process according to claim 25 wherein said acid or
anhydride or ester is obtained by the reaction of an olefin polymer
of 900 to 3,000 number average molecular weight and having one
terminal double bond per polymer chain with maleic anhydride.
30. The process according to claim 28 wherein said amino-1-alkanol
is 2-amino-2-methyl-1,3-propane-diol.
31. The process according to claim 28 wherein said amino-1-alkanol
is tris-hydroxy-methylaminomethane.
Description
BACKGROUND OF THE INVENTION AND PRIOR ART
During the past decade, ashless sludge dispersants have become
increasingly important, primarily in improving the performance of
lubricants and gasoline in keeping the engine clean of deposits and
permitting extended crankcase oil drawn periods. Most commercial
ashless dispersants fall into several general categories. In one
category, an amine or polyamine is attached to a long chain
hydrocarbon polymer, usually polyisobutylene, directly by reaction
of halogenated olefin polymer with polyamine as in U.S. Pat. Nos.
3,275,554; 3,565,592; 3,565,804. In another category, a polyamine
is linked to the polyisobutylene through an acid group, such as
long chain monocarboxylic acid, e.g., see U.S. Pat. No. 3,444,170
or long chain dicarboxylic acid such as polyisobutenylsuccinic
anhydride, by forming amide or imide linkages, such as described in
U.S. Pat. Nos. 3,172,892; 3,219,666; etc. More recently,
non-nitrogen ashless dispersants have been formed by esterifying
long chain dicarboxylic acids; such as the polyisobutenylsuccinic
anhydride, with polyols, such as pentaerythritol, as in U.S. Pat.
No. 3,381,022.
Reaction products of hydrocarbon substituted succinic anhydride,
e.g., the aforesaid polyisobutenylsuccinic anhydride, with
compounds containing both an amine group and a hydroxy group have
been suggested or investigated in the prior art. For example, U.S.
Pat. No. 3,272,746 teaches the reaction of ethanolamine and
diethanolamine, as well as various hydroxyalkyl substituted
alkylene amines, such as N-(2-hydroxyethyl) ethylene diamine,
N,N'-bis(2-hydroxyethyl) ethylene diamine, with alkenyl succinic
anhydride to obtain ashless dispersants for lube oil. A hydroxy
amine, such as diethanolamine, is reacted with a long chain
alkenylsuccinic anhydride in U.S. Pat. No. 3,324,033 to form a
mixture of esters and amides, wherein some of the diethanolamine
reacts through a hydroxy group to give an ester linkage, which
another portion of the diethanolamine forms an amide linkage. U.S.
Pat. No. 3,364,001 teaches a tertiary alkanolamine reacted with an
alkenyl succinic anhydride to form an ester useful as a gasoline
additive. U.S. Pat. No. 3,448,049 teaches dispersants, corrosion
inhibitors and antiwear agents in lubricants and fuels by
esterifying alkenyl succinic anhydride with a hydroxy compound made
by reacting an alkanolamine with an unsaturated ester, amide or
nitrile. U.S. Pat. No. 3,630,904 teaches reacting a hydroxy amine
with both short and long chain dicarboxylic acid. U.S. Pat. No.
3,484,374 teaches the polymeric condensation product of
polycarboxylic acid or anhydride with various alkanolamines such as
aminoethyl ethanolamine, N-methyldiethanolamine, etc.
U.S. Pat. No. 3,576,743 teaches reacting polyisobutenylsuccinic
anhydride with a polyol, such as pentaerythritol, followed by
reaction with tris-methylolaminomethane (THAM), (see Example 1).
U.S. Pat. No. 3,632,511 teaches reacting polyisobutenylsuccinic
anhydride with both a polyamine and a polyhydric alcohol including
THAM. U.S. Pat. No. 3,697,428 (Example 11) teaches reacting
polyisobutenylsuccinic anhydride with a mixture of pentaerythritol
and THAM.
SUMMARY OF THE INVENTION
As noted above, the prior art teaches dispersants formed from long
chain hydrocarbyl substituted dicarboxylic acid material, usually
alkenyl succinic anhydride, reacted with various amino or hydroxy
compounds, either through an amide, imide, or ester linkage. In
contrast to the prior art, the present invention is based upon the
discovery that reaction of long chain hydrocarbyl dicarboxylic acid
material, i.e., acid, or anhydride, or ester, with certain classes
of amino alcohols, under certain conditions, will result in a
different type of linkage, namely an oxazoline linkage, and that
materials with this oxazoline linkage appear very effective as
detergents or dispersants for oleaginous compositions such as lube
oil and gasoline.
THE HYDROCARBYL DICARBOXYLIC ACID MATERIAL
The long chain hydrocarbyl substituted dicarboxylic acid material,
i.e., acid or anhydrie, or ester, used in the invention includes
alpha-beta unsaturated C.sub.4 to C.sub.10 dicarboxylic acids, or
anhydrides or esters thereof, such as fumaric acid, itaconic acid,
maleic acid, maleic anhydride, chloromaleic acid, dimethyl
fumarate, etc. which are substituted with a long hydrocarbon chain,
generally a olefin polymer chain.
In general, these hydrocarbyl substituted dicarboxylic acid
materials and their preparation are well known in the art, for
example see U.S. Pat. Nos. 3,219,666; 3,172,892; 3,272,746; as well
as the aforementioned prior art patents.
The hydrocarbyl portion should average at least 50 aliphatic carbon
atoms per dicarboxylic acid group and be substantially saturated.
Usually no more than 10 mole %, and preferably 5 mole % or less, of
the total carbon to carbon linkage will be unsaturated, as
excessive unsaturation in the final product will tend to oxidize
and unduly form gums and resins in the engine. Further descriptions
and examples of the hydrocarbyl substituent portion are set forth
in U.S. Pat. No. 3,272,746, column 2, line 35 to column 4, line 10,
which is hereby incorporated in this application by reference.
Frequently these hydrocarbyl substituted dicarboxylic acid
materials are prepared by reacting the unsaturated dicarboxylic
acid material, usually maleic anhydride, with an olefin, usually an
olefin polymer still retaining a terminal unsaturation. The olefin
polymer can, if desired, be first halogenated, for example,
chlorinated or brominated to about 2 to 5 wt. % chlorine, or about
4 to 8 wt. % bromine, based on the weight of polymer, and then
reacted with the maleic anhydride (see U.S. Pat. No.
3,444,170).
In some cases, the olefin polymer may be completely saturated, for
example an ethylene-propylene copolymer made by a Ziegler-Natta
synthesis using hydrogen as a moderator to control molecular
weight. In the case of such saturated polymers, then the polymer
can be halogenated to make it reactive so it can be condensed with
the unsaturated dicarboxylic acid material which is then randomly
added along the polymer chain.
Preferred olefin polymers for reaction with the unsaturated
dicarboxylic acids are polymers comprising a major molar amount of
C.sub.2 to C.sub.5 monoolefin, e.g., ethylene, propylene, butylene,
isobutylene and pentene. The polymers can be homopolymers such as
polyisobutylene, as well as copolymers of two or more of such
olefins such as copolymers of: ethylene and propylene; butylene and
isobutylene; propylene and isobutylene; etc. Other compolymers
include those in which a minor molar amount of the copolymer
monomers, e.g., 1 to 20 mole %, is a C.sub.4 to C.sub.18
non-conjugated diolefin, e.g., a copolymer of isobutylene and
butadiene; or a copolymer of ethylene, propylene and 1,4-hexadiene;
etc.
The olefin polymers will usually have number average molecular
weights within the range of about 750 and about 200,000, more
usually between about 1000 and about 20,000. Particularly useful
olefin polymers have number average molecular weights within the
range of about 900 and about 3000 with approximately one terminal
double bond per polymer chain. An especially valuable starting
material for a highly potent dispersant additive made in accordance
with this invention is polyisobutylene.
Especially useful when it is desired that the dispersant additives
also possess viscosity index improving properties are 10,000 to
200,000, e.g., 25,000 to 100,000 number average molecular weight
polymers. An especially preferred example of such a V.I. improving
polymer is a copolymer of about 30 to 85 mole % ethylene, about 15
to 70 mole % C.sub.3 to C.sub.5 mono-alphaolefin, preferably
propylene, and 0 to 20 mole % of a C.sub.4 to C.sub.14
non-conjugated diene.
These ethylene-propylene V.I. improving copolymers or terpolymers
are usually prepared by Ziegler-Natta synthesis methods, e.g., see
U.S. Pat. No. 3,551,336. Some of these copolymers and terpolymers
are commercially available, such as VISTALON.RTM., an elastomeric
terpolymer of ethylene, propylene and 5-ethylidene norbornene,
marketed by Exxon Chemical Co., New York, N.Y. and NORDEL.RTM., a
terpolymer of ethylene, propylene and 1,4-hexadiene marketed by
E.I. duPont DeNemours & Co.
Other halogenation techniques for attaching the dicarboxylic acid
material to a long hydrocarbon chain, involve first halogenating
the unsaturated dicarboxylic acid material and then reacting with
the olefin polymer, or by blowing halogen gas, e.g., chlorine,
through a mixture of the polyolefin and unsaturated dicarboxylic
acid material, then heating to 150.degree. to 220.degree. C. in
order to remove HCl gas, e.g., see U.S. Pat. Nos. 3,381,022 and
3,565,804.
THE AMINO ALCOHOL
The amino alcohol used to make the oxazoline dispersant is a
2,2-disubstituted-2-amino-1-alkanol, having 2 to 3 hydroxy groups,
containing a total of 4 to 8 carbon atoms, and which can be
represented by the formula: ##STR1## wherein X is an alkyl, or
hydroxy alkyl group, with at least one of the X substituents, and
preferably both of the X substituents, being a hydroxy alkyl group
of the structure --(CH.sub.2).sub.n OH, wherein n is 1 to 3.
Examples of such 2,2-disubstituted amino alkanols, include
2-amino-2methyl-1,3-propanediol,
2-amino-2-(hydroxymethyl)-1,3-propanediol (also known as
tris-hydroxyaminomethane or THAM), 2-amino-2-ethyl-1,3-propanediol,
etc. Because of its effectiveness, availability, and cost, the THAM
is particularly preferred.
THE OXAZOLINE REACTION CONDITIONS
The formation of the novel oxazoline dispersants, in a fairly
higher yield, can be effected by adding about 1 to 2 mole
equivalent of the aforesaid 2,2-disubstituted-2-amino-1-alkanol per
mole equivalent of the dicarboxylic acid material, with or without
an inert diluent, and heating the mixture at
140.degree.-240.degree. C., preferably 180.degree.-220.degree. C.
for 1/2 to 24, more usually 2 to 8 hours.
Although not necessary, the presence of small amounts, such as 0.01
to 2 wt. %, preferably 0.1 to 1 wt. %, based on the weight of the
reactants, of a metal salt can be used in the reaction mixture as
catalyst to shorten the reaction times. The metal catalyst can
later be removed by filtration or by washing a hydrocarbon solution
of the product with a lower alcohol, such as methanol, ethanol,
isopropanol, etc., or an alcohol/water solution.
Alternatively, the metal salt can be left in the reaction mixture,
as it appears to become stably dispersed, or dissolved, in the
reaction product, and, depending on the metal, it may even
contribute performance benefits to the oil or gasoline. This is
believed to occur with the use of zinc catalysts.
Inert solvents which may be used in the above reaction include
hydrocarbon oils, e.g., mineral lubricating oil, kerosene, neutral
mineral oils, xylene, halogenated hydrocarbons, e.g., carbon
tetrachloride, dichlorobenzene, tetrahydrofuran, etc.
Metal salts that may be used as catalysts in the invention include
carboxylic acid salts of Zn, Co, Mn and Fe. Metal catalysts derived
from strong acids (HCl, sulfonic acid, H.sub.2 SO.sub.4, HNO.sub.3,
etc.) and bases tend to diminish the yield of the oxazoline
products and instead favor imide or ester formation. For this
reason, these strong acid catalysts or basic catalysts are not
preferred and usually will be avoided. The carboxylic acids used to
prepare the desired catalysts, include C.sub.1 to C.sub.18, e.g.,
C.sub.1 to C.sub.8, acids, such as the saturated or unsaturated
mono and dicarboxylic aliphatic hydrocarbon acids, particularly
fatty acids. Specific examples of such desired carboxylic acid
salts include zinc acetate, zinc formate, zinc propionate, zinc
stearate, manganese (ous) acetate, iron tartrate, cobalt (ous)
acetate, etc. Completion of the oxazoline reaction can be readily
ascertained by using periodic infrared spectral analysis for
following the oxazoline formation (oxazoline peak forms at 6.0
microns), or by the cessation of water evolution.
REACTION MECHANISM OF THE OXAZOLINE FORMATION
While not known with complete certainty, but based on experimental
evidence, it is believed that the reaction of the hydrocarbyl
substituted dicarboxylic acid material, e.g., a hydrocarbyl
substituted succinic anhydride, with the amino alcohol of the
invention, e.g., two equivalents of
2,2-disubstituted-2-aminoethanol such as tris-(hydroxymethyl)
aminomethane (THAM), gives oxazoline, e.g., bis-oxazolines, via the
intermediary of several discrete reaction species. If an acid
anhydride is used, the initial transformation appears to involve
the scission of the anhydride by the amino function of one mole of
the amino alcohol to yield an amic acid. Addition of another mole
equivalent of amino alcohol is believed to form the amic acid amine
salt, which then upon further heating, undergoes cyclo-dehydration
to the final bis-oxazoline product. The catalyst effect of metal
salts, such as zinc acetate (ZnAc.sub.2), on oxazoline formation is
very likely ascribable to the favorable polarization of the amide
group by the zinc ion towards attack by the hydroxy function of the
amino alcohol reactant. These reactions can be typified as follows
in the case of bis-oxazoline: ##STR2## where R is the hydrocarbyl
group of the succinic anhydride, and each X in this case of using
tris-(hydroxymethyl) amino methane (THAM) represents a --CH.sub.2
OH group.
In contrast to the above oxazoline formation using the
disubstituted amino alcohol, if the amino alcohol has no
substituents as in 2-aminoethanol, or has only one substituent in
the 1- or 2-position as in 2-amino-1-propanol, 2-amino-1-butanol,
and related mono-substituted 2-aminoethanols, the amino alcohol
fails to undergo the aforesaid oxazoline reaction. Instead, these
other amino alcohols will react with the succinic anhydride to give
almost exclusively succinimide products as illustrated in the
following reaction. ##STR3## wherein R and X are as previously
defined. In experiments on the above reactions, in no instance were
discernible amounts of bis-oxazoline products found.
USE OF THE OXAZOLINE ADDITIVE IN OLEAGINOUS COMPOSITIONS
The oil soluble oxazoline reaction products of this invention can
be incorporated in a wide variety of oleaginous compositions. They
can be used in lubricating oil compositions, such as automotive
crankcase lubricating oils, automatic transmission fluids, etc. in
concentrations generally within the range of about 0.01 to 20
weight percent, e.g., 0.1 to 10 weight percent, preferably 0.3 to
3.0 weight percent, of the total composition. The lubricants to
which the oxazoline products can be added include not only
hydrocarbon oils derived from petroleum, but also include synthetic
lubricating oils such as polyethylene oils; alkyl esters of
dicarboxylic acid; complex esters of dicarboxylic acid, polyglycol
and alcohol; alkyl esters of carbonic or phosphoric acids;
polysilicones; fluorohydrocarbon oils; mixtures of mineral
lubricating oil and synthetic oils in any proportion, etc.
When the products of this invention are used as detergents or
dispersants in fuels such as gasoline, kerosene, diesel fuels, No.
2 fuel oil and other middle distillates, a concentration of the
additive in the fuel in the range of 0.001 to 0.5 weight percent,
based on the weight of the total composition, will usually be
employed.
When used as an antifoulant in oil streams in refinery operations
to prevent fouling of process equipment such as heat exchangers,
about 0.001 to 2 wt. % will generally be used.
The additive may be conveniently dispensed as a concentrate
comprising a minor proportion of the additive, e.g., 2 to 45 parts
by weight, dissolved in a major proportion of a mineral lubricating
oil, e.g., 98 to 45 parts by weight, with or without other
additives being present.
In the above compositions of concentrates, other conventional
additives may also be present, including dyes, pour point
depressants, antiwear agents such as tricresyl phosphate or zinc
dialkyl dithiophosphates of 3 to 8 carbon atoms in each alkyl
group, antioxidants, such as N-phenyl .alpha.-naphthylamine,
tert-octyl phenol sulfide, 4,4'-methylene bis(2,6-di tert-butyl
phenol), viscosity index improvers such as ethylene-propylene
copolymers, polymethacrylates, polyisobutylene, alkyl
fumarate-vinyl acetate copolymers and the like, as well as other
ashless dispersants, detergents and viscosity index improvers,
etc.
This invention will be further understood by reference to the
following examples, which include preferred embodiments of the
invention.
EXAMPLE 1
A bis oxazoline of polyisobutenylsuccinic anhydride and
tris-(hydroxymethyl) aminomethane was prepared as follows:
280 gms. (0.5 equivalent) of polyisobutenylsuccinic anhydride was
charged into a laboratory glass 1 liter reaction flask, equipped
with a bottom draw-off, a thermometer, a charging funnel, a
nitrogen bleed, and an overhead condensor equipped with a
Deane-Starke water trap. The flask was heated in an oil bath. The
anhydride was then heated to about 200.degree. C. under a blanket
of nitrogen. While stirring at this temperature, 0.5 mole (60.5 g.)
of tris-(hydroxymethyl) aminomethane (THAM) was added in a series
of portions of about 5 grams each, over an hour period with
stirring. Thereafter, the reaction was continued with stirring at
200.degree. C. for 2 hours while collecting water from the
condenser. The flask was then allowed to cool and a liter of hexane
was added to the flask to dissolve the reaction product, which was
then drained from the flask and filtered through filter paper to
remove any solids. The hexane solution was then washed three times
with 250 ml. portions of methanol. Thereafter the hexane layer was
placed in a rotoevaporator at 90.degree. C. for about 2 hours to
evaporate off the hexane. Then an equal weight of a neutral mineral
lubricating oil having a viscosity of about 150 SUS at 100.degree.
F. (Solvent 150 Neutral) was added with stirring to give an oil
concentrate consisting of about 50 wt. % of the oxazoline reaction
product in about 50 wt. % mineral lubricating oil. The infrared
spectrum of this concentrate product featured a strong absorption
band at about 6.0 microns as expected for the bis-oxazoline. The
product (50% active ingredient in Solvent 150 Neutral Oil) analyzed
for 0.78 wt. % nitrogen and 2.30 wt. % oxygen. The observed oxygen
to nitrogen (O/N) ratio of 2.95 is in excellent agreement with the
theoretical O/N ratio of 3. The product showed a total acid number
(ASTM-D664) of 0.03.
The polyisobutenylsuccinic anhydride used above had been prepared
by conventional techniques, namely the reaction of chlorinated
polyisobutylene having a chlorine content of about 3.8 wt. %, based
on the weight of chlorinated polyisobutylene, and an average of 70
carbon atoms in the polyisobutylene group, with maleic anhydride at
about 200.degree. C. The resulting polyisobutenyl succinic
anhydride showed a saponification number (Sap. No.) of 80 mg
KOH/gm.
EXAMPLE 2
A mixture of 500 gm. (0.78 equivalent) of polyisobutenylsuccinic
anhydride having a Sap No. of 87, 500 ml. of tetrahydrofuran (THF)
as solvent, 4 gm. of zinc acetate dihydrate (ZnAc.sub.2.2H.sub.2 O)
as a catalyst and 96.8 gm. (0.8 mole) of tris-(hydroxymethyl)
aminomethane (THAM) was charged into the previously described glass
reactor and heated. When the reaction temperature had risen to
72.degree. C., the THF solvent distilled off. Further heating at
about 200.degree. C. for four hours gave the expected quantity of
water, i.e., about 1.1 moles of water in the trap. After
filtration, the reaction product analyzed for 1.99 wt. % nitrogen,
and 0.12 wt. % zinc. The product was drawn from the flask and
diluted with an equal weight of the Solvent 150 Neutral mineral
lubricating oil for testing in the Sludge Inhibition Bench (SIB)
test to be later described.
The polyisobutenyl group of the succinic anhydride averaged about
70 carbon atoms.
EXAMPLE 3
A mixture of 500 gm. (0.78 equivalent) of the
polyisobutenylsuccinic anhydride of Example 2, 96.8 gm. (0.8 moles)
of tris-(hydroxymethyl) aminomethane and 4.0 gms. of zinc acetate
dihydrate were charged into the glass reactor previously described.
The mixture was heated in the oil bath at about
200.degree.-220.degree. C. for about three hours, until water
ceased to evolve from the reactor. Approximately 18.0 gm. (1 mole)
of water collected in the trap. The infrared spectrum of the
reaction product drawn from the flask showed a strong absorption
band at 6.0 microns showing the oxazoline structure had formed.
Elemental analysis showed that the final product of 50 wt. % of the
reaction product dissolved in 50 wt. % Solvent 150 Neutral oil,
contained 1.08% nitrogen and 0.058% zinc.
EXAMPLE 4
A mixture of 60.57 pounds (44.0 moles) of polyisobutenylsuccinic
anhydride of Example 2, 11.73 pounds (27.5 moles) of THAM, and 0.48
pounds (1 mole) of zinc acetate dihydrate as catalyst, were charged
into a small pilot plant stirred reactor equipped with a nitrogen
purge, stirrer, and overhead condensor with a water trap. The
reaction mixture was heated to 427.degree. F. at a rate of
122.degree. F. per hour and held on temperature until 3.35 pounds
(ca. 84.49 moles) of water of reaction was produced. Thereafter,
the reaction contents were cooled and diluted with the aforesaid
Solvent 150 Neutral oil to give a 50 wt. % solution of the reaction
product in 50 wt. % oil. This oil concentrate showed a Hydroxyl
Number of 37.0 and contained 0.92 wt. % nitrogen and 0.05 wt. %
zinc, based on the weight of the concentrate.
EXAMPLES 5 to 23
Using the same general procedure as described in Example 3, various
polyisobutenylsuccinic anhydrides (PIBSA) of polyisobutylene having
number average molecular weights of 980, 2300 and 18,000 were
reacted with 2 mole equivalents of various amino alcohols to form
bis-oxazolines, including 2-amino-2-methyl-1-propanol (AMP),
2-amino-2-methyl-1,3-propane-diol (AMPD) and
2-amino-2-(hydroxymethyl)-1,3-propanediol (THAM).
The reactants, proportions, and analyses of the products formed in
Examples 1 to 23 are summarized in Table I.
TABLE I
__________________________________________________________________________
OXAZOLINE ADDUCTS OF POLYISOBUTENYLSUCCINIC ANHYDRIDE AND
2,2-DISUBSTITUTED-2-AMINO ETHANOLS Analyses of PIBSA Amino Alcohol
Zinc Salt.sup.(c) Concentrate.sup.(d) PIB Grams Grams Grams % Wt. %
Wt. % Wt. Example Mw.sup.(a) Sap. No. Used Type.sup.(b) Used Used N
Zn O.sub.2
__________________________________________________________________________
1 980 80 280 THAM 60.5 0 .78 0 2.30 2 980 87 500 THAM 96.8 4.0 1.99
0.12 -- 3 980 87 500 THAM 96.8 4.0 1.08 0.058 -- 4 980 84 27,500
THAM 5,300 220 .92 .05 -- 5 980 80 500 AMP 71.2 4 0.89 0.07 -- 6
980 112 500 AMP 100.0 4 1.16 .01 -- 7 980 112 150 AMP 26.8 0 .90 --
1.10 8 980 112 150 AMP 28 0 .95 -- 1.60 9 980 80 350 AMPD 79 1.4 --
-- -- 10 980 80 500 THAM 96.8 4.0 .99 0.12 -- 11 980 80 350 THAM
60.5 2.7 0.93 .017 -- 12 980 80 350 THAM 60.5 0 1.15 -- -- 13 980
112 150 THAM.sup.(e) 36.3 0 1.18 -- -- 14 980 112 500 THAM.sup.(e)
121 0 1.2 -- 3.58 15 980 112 2000 THAM.sup.(e) 484 0 1.38 -- 3.31
16 980 112 600 THAM.sup.(e) 145.2 4 1.17 -- 3.57 17 980 112 500
THAM.sup.(e) 121 4 1.19 .01 -- 18 980 112 500 THAM 121 4 1.28 .06
-- 19 980 112 520 THAM 121 0 1.43 -- -- 20 980 80 350 THAM .8 1.31
1.18 -- -- AMP 24.51 21 18,000 1.9 200.sup.(f) THAM .86 0.07 -- --
-- 22 18,000 1.9 200.sup.(f) THAM .73 0.08 -- -- -- 23 18,000 1.9
2000.sup.(f) THAM 7.3 0.8 -- -- --
__________________________________________________________________________
.sup.(a) Molecular weight of the polyisobutenyl group (PIB) by
Vapor Pressure Osmometry (VPO) ##STR4## ##STR5## - THAM = NH.sub.2
C(CH.sub.2 OH).sub.3 .sup.(c) Zinc diacetate dihydrate. .sup.(d)
Analyses on 50 wt. % solution of the oxazoline reaction product in
50 wt. % Solvent 150 Neutral mineral lubricating oil. .sup.(e) THF
used to dissolve THAM. .sup.(f) 20 wt. % solution in S 150 N.
.sup.(g) 30.3 gm. of THAM added over 1 hour, then 24.51 of AMP
added over 1 hour.
SLUDGE INHIBITION BENCH (SIB) TEST
A number of the additives of this invention were subjected to a
Sludge Inhibition Bench (SIB) Test which has been found, after a
large number of evaluations, to be an excellent test for assessing
the dispersing power of lubricating oil dispersant additives.
The medium chosen for the Sludge Inhibition Bench Test was a used
crankcase mineral lubricating oil composition having an original
viscosity of about 325 SUS at 100.degree. F. that had been used in
a taxicab that was driven generally for short trips only, thereby
causing a buildup of a high concentration of sludge precursors. The
oil that was used contained only a refined base mineral lubricating
oil, a viscosity index improver, a pour point depressant and zinc
dialkyldithiophosphate antiwear additive. The oil contained no
sludge dispersants. A quantity of such used oil was acquired by
draining and refilling the taxicab crankcase at 1000-2000 mile
intervals.
The Sludge Inhibition Bench Test is conducted in the following
manner. The aforesaid used crankcase oil, which is milky brown in
color, is freed of sludge by centrifuging for 1 hour at about
39,000 gravities (gs.). The resulting clear bright red supernatant
oil is then decanted from the insoluble sludge particles thereby
separated out. However, the supernatant oil still contains
oil-soluble sludge precursors which on heating under the conditions
employed by this test will tend to form additional oil-in-soluble
deposits of sludge. The sludge inhibiting properties of the
additives being tested are determined by adding to portions of the
supernatant used oil, a small amount, such as 0.3, 0.5, 1 or 2
weight percent, on an active ingredient basis, of the particular
additive being tested. Ten grams of each blend being tested is
placed in a stainless steel centrifuge tube and is heated at
280.degree. F. for 16 hours in the presence of air. Following the
heating, the tube containing the oil being tested is cooled and
then centrifuged for 30 minutes at about 39,000 gs. Any deposits of
new sludge that form in this step are separated from the oil by
decanting the supernatant oil and then carefully washing the sludge
deposits with 25 ml. of pentane to remove all remaining oil from
the sludge. Then the weight of the new solid sludge that has been
formed in the test, in milligrams, is determined by drying the
residue and weighing it. The results are reported as milligrams of
sludge per 10 grams of oil, thus measuring differences as small as
1 part per 10,000. The less new sludge formed the more effective is
the additive as a sludge dispersant. In other words, if the
additive is effective, it will hold at least a portion of the new
sludge that forms on heating and oxidation, stably suspended in the
oil so it does not precipitate down during the centrifuging.
Using the above described test, the dispersant action of oxazoline
additives of the present invention was compared with the dispersing
power of a commercial dispersant referred to as PIBSA/TEPA. The
PIBSA/TEPA was prepared by reaction of 1 mole of tetraethylene
pentamine with 2.8 moles of polyisobutenylsuccinic anhydride
obtained from polyisobutylene of about 1000 number average
molecular weight. The PIBSA/TEPA dispersant was used in the form of
an additive concentrate containing about 50 weight percent
PIBSA/TEPA in 50 wt. % mineral lubricating oil. This PIBSA/TEPA
additive concentrate analyzed about 1.14% nitrogen, indicating that
the active ingredient, i.e., PIBSA/TEPA per se, contained about
2.28% nitrogen. Sufficient quantities of all the additive
concentrates tested below were used in making the test blends to
furnish the 1.0, 0.5, and 0.3 weight percent of actual additive.
The test results are given in Table II.
TABLE II ______________________________________ SLUDGE DISPERSANCY
TEST RESULTS Additive of Mg. Sludge/10 g. Oil at Example 1.0 Wt. %
0.5 Wt. % 0.3 Wt. % ______________________________________ 10 1.6
6.6 -- 15 3.5 -- -- 14 3.8 -- -- 12 2.9 5.9 7.3 11 2.7 6.1 7.3 21
2.6 5.9 -- 22 2.8 6.3 -- 23 2.0 4.1 -- PIBSA- 5.2 7.5 7.7 TEPA
______________________________________
It will be noted from Table II that the dispersants of the
invention were more effective than the commercial PIBSA/TEPA
dispersant which is in widespread use in crankcase lubricating
formulations. Specifically 1.0 wt. % of PIBSA/TEPA per se (i.e., 2
wt. % of its 50 wt. % concentrate) gave 5.2 mg. of new sludge
precipitated, per 10 gms. of crankcase oil. On the other hand, the
bis-oxazoline products of the invention shown in Table II, were
more effective as sludge dispersants since they stably suspended a
larger proportion of the new sludge as shown by the fact that less
sludge precipitated down during the centrifugation. Similar results
are shown at the 0.5 wt. %, and 0.3 wt. % active ingredient
levels.
ENGINE TESTS
Lubricant A -- This was a SAE Grade 30 crankcase lubricant
formulation for automotive crankcase application that was used as a
reference. The reference formulation contained mineral lubricating
oil, 4.68 wt. % of the aforesaid PIBSA-TEPA ashless dispersant
concentrate, and a series of conventional additives, namely, a
P.sub.2 S.sub.5 treated alpha pinene as an oxidation, corrosion
inhibitor; and as detergent inhibitor additives, a zinc dialkyl
dithiophosphate, barium sulfonate, and an overbased barium
detergent comprising barium carbonate formed in the presence of
P.sub.2 S.sub.5 treated polyisobutylene and alkyl phenol as
surfactants; along with an anti-rust additive.
Lubricants B to E -- These lubricants were indentical with
Lubricant A described above, except that the 4.68 wt. % of the 50
wt. % concentrate of the PIBSA-TEPA ashless dispersant was omitted,
and the inventive oxazoline dispersant of Example 4 was used in
varying amounts as follows: Lubricant B -- 4.68 wt. %; Lubricant C
-- 3.76 wt. %; Lubricant D -- 3.25 wt. % and Lubricant E -- 2.75
wt. % of the 50 wt. % concentrate of oxazoline of Example 4.
Lubricants A to E described above were tested in a MS Sequence VC
Engine Test, which is well known in the automotive industry, being
described in the publication entitled "Multicylinder Test Sequences
for Evaluating Automotive Engine Oils" which is ASTM Special
Publication 315-E. At the end of each test, various parts of the
engine are rated on a merit basis of 0 to 10, wherein 10 represents
a perfectly clean part while the lesser numbers represent
increasing degrees of deposit formation. The various ratings are
then totaled and averaged on a basis of 10 as a perfect rating. The
results obtained with the compositions described above are given in
Table III.
TABLE III
__________________________________________________________________________
MS SEQUENCE VC TEST RESULTS Merit Ratings (Basis 0 to 10) Lubricant
A B C D E
__________________________________________________________________________
Sludge Merit 9.2/9.2 9.5 9.2 9.0 8.5 Varnish Merit 8.2/7.7 8.8 8.2
8.4 8.0 Piston Skirt Varnish Merit 8.4/7.9 8.8 8.7 8.4 8.6
PIBSA-TEPA (50% a.i., i.e., 4.68% -- -- -- -- active ingredient)
Example 4 (50% a.i., i.e., -- 4.68% 3.76% 3.25% 2.75% active
ingredient)
__________________________________________________________________________
As seen by Table III, two engine runs were made on the PIBSA-TEPA
containing formulation. However, taking the better of the two runs
on Lubricant A, it is seen that the bix-oxazoline dispersant of
Example 4 was superior at the 4.68 and the 3.76 wt. %
concentrations, indicating the higher effectiveness of the
oxazoline. Considering varnish, the oxazoline was as effective as
the PIBSA-TEPA even at the 3.25 wt. % level, and almost as
effective at the 2.75 wt. % level (i.e., 1.38 wt. % actual
ingredient). Thus, in an important industry test, the oxazoline
dispersants were very effective. These engine test results shown
that the oxazoline additive c this invention, was not only a good
sludge dispersant as shown by Sludge Merit, but also possesses good
oxidation control as shown by the reduction in varnish deposits
(Varnish Merit) on the various engine parts, and particularly on
the piston skirts (Piston Skirt Varnish Merit). This favorable
antioxidant property of the oxazoline dispersant additive
diminishes the need for additional conventional antioxidants.
Lubricants A and B were tested in the Caterpillar 1-H test
(MIL-L-2104B). Following in Table IV are the results of two such
engine tests on each Lubricant, showing the piston cleanliness.
TABLE IV ______________________________________ CATERPILLAR 1-H
TEST - 480 HOURS Lubricant A B Requirements.sup.(1)
______________________________________ TGF(%) 13/28 18/4 30 max.
2nd groove 24/3 0/10 30 max. 1st Land 16/16 7/3 60 max. Below 0/0
6/0 0 Rating Pass/Pass BLPass/Pass
______________________________________ .sup.(1) Requirements are
estimates, actually certification of a piston i done by inspection
and some variations from the limit shown are allowed based on the
total condition of the piston.
As seen by Table IV, Lubricant B containing the oxazoline
dispersant gave exceptionally low deposits as indicated by the %
top groove fill (TFG), the amount of deposit in the second ring
groove, and the deposits on the first land area, although one of
the two runs was a borderline pass (B/L pass) due to deposits below
the second groove (Below). This, however, can be overcome by
changes in the formulation.
EXAMPLE 24
Part A -- 350 gms. (0.328 moles) of polyisobutenylsuccinic
anhydride having an ASTM saponification number of about 105 and a
molecular weight of about 1067 was reacted with 79.4 gms. (0.656
moles) of 2-amino-2-(hydroxymethyl) 1,3-propanediol (THAM) as
follows: the polyisobutenylsuccinic anhydride and THAM were
dissolved in 250 ml xylene in a 2 liter 4-neck flask equipped with
thermometer, stirrer, dropping funnel, a condenser including a
Deane-Starke water trap, and having a nitrogen bleed to provide a
nitrogen blanket. The heat was raised to about 290.degree. to
306.degree. F. and over a period of one hour and 45 minutes, about
9 cc water collected in the trap. The heat was then turned off
overnight and the following day the reaction mixture was refluxed
another hour at 308.degree. F. wherupon 10 cc of water had now
collected in the trap. The reaction mixture was then sparged with
nitrogen to evaporate the xylene during which time the temperature
rose to 380.degree. F. Then the system was connected to a vacuum
pump and heated to about 360.degree.-380.degree. F. for 3 hours
under a pressure of about 20-30 mm. Hg. The heat was then turned
off overnight. The following day the mixture, which was not free of
xylene, was warmed to 200.degree. F. and 489 cc (419 gm.) xylene
was added to make a concentrate containing 50 wt. % of the
bis-oxazoline reaction product dissolved in the xylene to give a
concentrate having a nitrogen content of 1.23 wt. % against
calculated nitrogen content of 1.1 wt. %.
Part B -- A sample of the concentrate product of Part A above was
added to a gasoline in an amount equivalent to 25 lbs. of the
concentrate (50% a.i.) per 1000 barrels of gasoline. This additive
treated gasoline was then tested for its effectiveness in a
carburetor detergent test described as follows.
The test gasoline was a MS-08 gasoline which contained about 0.8
wt. % sulfur and which accelerated the formation of carburetor
deposits. The tests was carried out by operating a specially fitted
280 cubic inch displacement V-8 test engine fitted with two
separate carbutetors leading to opposite manifolds on either side
of the engine. Blowby from the engine was cycled back to the intake
of the carburetors. In each carburetor was a metal sleeve which
could be readily removed and weighed to determine the amount of
deposits that has accumulated on the sleeve. The engine was
operated for 24 hours under no load through a test cycle of 8
minutes idle at 700 rpm, and then 30 seconds at 2500 rpm, followed
by repeating the cycle. During the first 12 hours of the test, the
one carburetor (hereinafter call the first carburetor) was operated
on the untreated gasoline, while the other carburetor (hereinafter
called the second carburetor) was operated on the gasoline
containing the additive. At the end of this 12 hour period, the
sleeves were removed, weighed, and then replaced. During the next
twelve hours of operation the feed to the two carburetors was
reversed so that the first carburetor now operated on the additive
treated gasoline, while the second carburetor operated on the
nonadditive gasoline. The sleeves were again removed and weighed.
The % carburetor cleanup due to the additive was calculated as
follows: the change in weight of the two sleeves during their run
with the untreated gasoline were added together (first total) and
from this value was subtracted the sum of the change in weight of
the two sleeves during their cleanup period while operating on the
additive treated gasoline (second total). The % carburetor cleanup
is then calculated as follows: ##EQU1##
In this case, the carburetor cleanup was 55% indicating that the
additive was very effective as a carburetor detergent when added to
gasoline.
Part C -- A SIB Test was carried out on the product of Part A,
above, to determine its effectiveness as a sludge dispersant in
lubricating oil. A set of two blanks, i.e., the SIB oil without
additive, was run first. The blanks gave 17.1 and 2.7 mg. sludge
per 10 grams of oil respectively. A second set of blanks gave 16.3
and 16.6 mg. sludge per 10 grams of oil, thus clearly indicating
that the aforesaid 2.7 reading was in error, and could be
disregarded. Blends in the SIB Test oil of 0.25 wt. % 0.50 wt. %
and 0.75 wt. % of the concentrate (50% oxazoline) of Part A, gave
sludge readings of 9.6, 0.3, and 0.1 mg. sludge/10 gm. of oil,
respectively. Since the oil without additive gave readings of
16-17, the treated oil showed that the oxazoline concentrate was
effective as a dispersant and extremely effective at the 0.50 and
0.75 wt. % concentrations.
The SIB Tests were repeated again at a later time. Here a set of 4
blanks, i.e., untreated oil, gave readings of 16.4, 17.2, 18.1 and
17.8 mg. sludge/10 gm. of oil, respectively. Two tests of the SIB
oil containing 0.25 wt. % of the concentrate of Part A gave
readings of 12.2 and 12.0. Two tests of the SIB oil containing 0.50
wt. % of said concentrate gave readings of 3.1 and 6.1. Tests at
0.75 wt. % and 1.0 wt. % concentrate levels each gave a reading of
0.1. 1.5 wt. % concentrate gave a reading of 0.7, and 2.0 wt. %
concentrate gave a reading of 0.6. All of said preceding readings
are in terms of mg. sludge per 10 grams of the test oil. This test
data confirms the preceding SIB test data on the bis-oxazoline
product of Part A above showing that it is an extremely effective
sludge dispersant, particularly at above the 0.75 wt. %
concentration level, i.e., about 0.375 wt. % active ingredient.
EXAMPLE 25
32 gm. (0.03 moles) of polyisobutenylsuccinic anhydride having a
molecular weight of about 1067 was reacted with 7.2 gms. (0.06
moles) of 2-amino-2-(hydroxymethyl)-1,3-propanediol by comoining
the reactants together in 100 ml. 3-neck stirred flask along with
25 ml. xylene. The temperature was raised to 200.degree. F. for 1
hour, then the heat was turned off and the mixture was allowed to
stir over a weekend. Following this the mixture was again heated to
200.degree. F. with 3 hours of stirring. The temperature was then
raised to 375.degree. F. and the contents were blown with nitrogen
to remove the xylene. After completion of the xylene removal, the
mixture was then vacuum stripped at 2 mm. Hg. pressure at
375.degree. F. for 3 hours to remove water that had formed. The
reaction mixture was allowed to cool overnight while the vacuum was
maintained. The following day the product was removed from the
flask. The product analyzed 2.22 wt. % nitrogen as against a
calculated value of about 2.20 wt. % nitrogen for the
bis-oxazoline.
The product of Example 25 was tested for its effectiveness as a
gasoline anti-rust agent. Since this oxazoline product was not
directly soluble in gasoline, it was first dissolved in xylene, and
sufficient xylene solution was then added to the gasoline to
incorporate the additive at a treat rate of 10 pounds of oxazoline
additive per thousand barrels of gasoline, i.e., about 0.024 wt. %.
The gasoline so treated was then tested for rust according to ASTM
D-665M rust test. In brief, this test is carried out by observing
the amount of rust that forms on a steel spindle after rotating for
an hour in a water-gasoline mixture. In this case, the oxazoline
treated gasoline gave no rust indicating that it was very effective
as an anti-rust additive since the untreated gasoline will give
rust over the entire surface of the spindle.
Several mono-oxazoline dispersants were prepared as follows:
EXAMPLE 26
Approximately 0.2 mole of polyisobutenylsuccinic anhydride (Sap.
No. 80) was charged into a reactor and heated to 205.degree. C.
under a nitrogen blanket. To the stirred reactant were added 0.2
mole (24.2 g.) of tris-(hydroxymethyl) aminomethane, in portions,
over an hour period. Thereafter, the mixture was stirred at
205.degree. C. for about 3 hours while water distilled from the
reactor. Upon cooling, half of the reaction mixture was dissolved
in an equal weight percent of Solvent 150 Neutral oil. The
resulting oil solution was then diluted with 500 ml. of hexane and
the resulting hexane solution was washed three times, each with a
250 ml. portion of methanol. Rotoevaporation of the hexane layer
afforded a concentrate which analyzed for 0.50 wt. % nitrogen and
2.37 wt. % oxygen, and featured a TAN (total acid number) of 0.16.
The experimentally found O/N ratio of 4.7 was in excellent
agreement with the theoretical O/N ratio of 4.6. Furthermore, a
strong absorption band at 6.0 microns in infrared spectrum of the
product indicated a mono-oxazoline structure formed. Another strong
absorption band at 5.75 micron indicated an ester structure had
also formed, which is believed to be between one of the hydroxy
groups extending from the oxazoline ring with a carboxy group of
the polyisobutenylsuccinic anhydride.
EXAMPLE 27
1335 grams of polyisobutenylsuccinic anhydride having a Sap. No. of
about 80 was charged into a 1 liter 4-necked flask, and heated to
205.degree. C. The reactant was stirred under a nitrogen sparge and
blanket and 121 grams of tris-(hydroxymethyl) aminomethane was
added over a 1 hour period, being careful to avoid foaming. The
course of reaction was monitored by infrared spectroscopy, which
indicated that the reaction was essentially complete after eight
hours. The neat product analyzed for 1.12 wt. % nitrogen and
featured a number average molecular weight of 3034 (by vapor
pressure osmometry). The infrared spectrum of the product showed
the expected ester and oxazoline bands at 5.75 and 6.02 microns,
respectively.
EXAMPLE 28
53.4 pounds of polyisobutenylsuccinic anhydride (PIBSA) with a Sap.
No. of about 80 was charged into a reactor and heated to
435.degree. F. Th PIBSA reactant was stirred and sparged with
nitrogen, and 4.84 pounds of tris-(hydroxymethyl) aminomethane were
added over an hour period. Reaction was continued until water
evolution had ceased. The product was diluted with an equal weight
of Solvent 150 Neutral oil and showed ester and oxazoline
absorptions in the infrared. The oil solution analyzed for 0.51 wt.
% nitrogen. Also there should be 50 to 1400 preferably about 60 to
300 carbon atoms per moiety of discarboxylic acid material. Thus,
in the case of very high molecular weight polymers, they will be
generally chlorinated to permit adding on a number of dicarboxylic
acid groups along the chain. For example, using a polymer with
10,000 carbon atoms, one could chlorinate and the react with maleic
anhydride so as to distribute about 50 maleic anhydride units
randomly along the polymer chain, and then convert these maleic
anhydride units into mono or bis-oxazoline units, or mixtures of
mono and bis-oxazoline units.
In summary, effective additives for oleaginous compositions can be
prepared by reaction of a hydrocarbon substituted dicarboxylic acid
material with a 2,2-disubstituted-2-amino-1-alkanol under
conditions such that formation of simple esters, imides or amides
is eliminated, or at least minimized, so that a substantial
proportion of the amino-alkanol is converted into oxazoline rings.
Infrared spectrum on some of the aforesaid Examples indicate that a
major proportion, and in some cases essentially all, of the
amino-alkanol was converted to oxazoline rings.
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